Self-loading/unloading lift truck carriage

ABSTRACT

An attachment device for use on fork-lift trucks in the form of an orbital carriage having the capability of drawing a palletless load onto itself, transporting the load to a new location and thence discharging the palletless load from itself, with no damage to the load resulting from excessive vibration or squeezing during the drawing, transporting, and discharging cycle.

United States Patent 1 Shaffer [111 3,737,060 1 June 5,1973

[54] SELF-LOADING/UNLOADING LIFT TRUCK CARRIAGE [75] Inventor: Walter M. Shaffer, Chesterland,

Ohio

[73] Assignee: Towmotor Corporation, Cleveland,

Ohio

[22] Filed: July 12, 1971 [21] Appl. No.: 161,647

52 U.S.Cl ..214/s14,214 7so 51 lnt.Cl. ..B60p 1/02 [58] FieldofSearch ..19s/219;214/7s0,

[56] References Cited UNITED STATES PATENTS 3/1959 Repke et al. ..2-14/750 Jannsen ..214 750 2,628,734 2/1953 2,633,260 3/1953 Sutherland ....214[750 7 3,392,858 7/1968 Primary ExaminerDrayton E. Hoffman Assistant ExaminerLawrence J Oresky Attorney-Charles M. Fryer, Amt H. Tjensvold,

Donald C. Feix et al.

[57] ABSTRACT An attachment device for use on fork-lift trucks in the v form of an orbital carriage having the capability of drawing a palletless load onto itself, transporting the load to a new location and thence discharging the palletless load from itself, with no damage to the load resulting from excessive vibration or squeezing during the drawing, transporting, and discharging cycle.

7 Claims, 6 Drawing Figures Fernstrom et a]. .1214/750 PATENTEDJUH 5 I975 3.737.060 SHEET 10F 5 INVENTOR WALTER M. SHAFFER ATTORNEYS PATENIEDJUH 5|975 3.737.060

SHEET 2 [IF HE HI INVENTOR WALTER M. SHAFFER J? W W 1 /s ne 135m PATENTEDJUH 51913 SHEET 3 OF INVENTOR WALTER M. SHAFFER ATTORNEYS SELF-LOADING/UNLOADING IJIFT TRUCK CARRIAGE BACKGROUND OF THE INVENTION It has long been a problem in commercial and industrial material-handling operations to handle bulk loads in a simple and economical manner. Commercial truckers prefer not to use conventional wooden or metal pallets to support unit loads because such pallets are expensive, have too muchweight and bulk, and

must be returned to the originating source for further usage. Also, truck freight is incompatible with pushpull devices normally associated with the newer cardboard pallets which have reduced some of the problems tempts to solve the thus-presented pallet problem, in-

dustry has typically adopted the system of using cardboard pallets for bagged and like material, along with a fork-lift truck equippedwith a gripping attachment for drawing such palletized material onto the carriage forks. An ejection device on the fork-lift truck carriage is required with this system to discharge the load from the forks.

Another common means used for picking up bagged material has been to utilize a load-clamping device which grips the sides of the load by hydraulicallyor mechanically-actuated clamps. This device has the inherent disadvantage of possibly damaging the load due to the truck operator incorrectly applying excessive clamping pressure. Various forkvibrating or oscillating devices have also been created; however, these have proven unsatisfactory in use due to the severe vibration transmitted to and consequently damaging the load.

SUMMARY OF THE INVENTION The present invention overcomes the above-noted problems by self-loading and unloading loads in the form of cartoned and bagged materials in such a manner that no damaging pressures or vibrations are transmitted to the such materials. The need for pallets to handle these cartoned or bagged materials is eliminated, thus greatly reducing the material-handling costs since expensive pallets no longer add weight to shipments, take up valuable space, or have to be returned to the sender for subsequent reuse. Some types of loads, such as bagged materials, may be more effectively handled through the use of a cardboard sheet placedunder such loads. This is 'much less expensive than using cardboard pallets in conjunction with forklift truck, push-pull devices.

OBJECTS OF THE INVENTION Accordingly, it is a primary object of this invention to provide a fork-lift truck carriage capable of drawing a load onto itself, supporting same for transport and thence discharging the load in a more efficient and less costly manner than is possible with any previouslyknown device.

Another object of this invention is to accomplish the above in such a manner that no damaging vibrations or pressures can be transmitted to the load.

It is also an object of this invention to eliminate the need for the use of pallets of any kind to handle cartoned or bagged materials.

It is a further object of this invention to provide a load-handling device that can also be used to accomplish normal fork-lift truck operations involving the use of conventional wooden or metal pallets.

A further object of this invention is to provide a device which utilizes at least one load-handling member that is actuateable in a curvilinear path to self-load and unload unpalletized material.

A still further object of this invention is to provide a device which utilizes at least one load-handling member that supports the load during the loading and unloading cycles and is movable only in the manner usually associated with standard fork-lift truck carriages.

BRIEF DESCRIPTION OF THE DRAWINGS Additional advantages and features of the present invention are made apparent in the following description and the accompanying drawings, wherein:

FIG. 1 is a side elevational view of a fork-lift truck having the load-handling device or carriage mounted thereon;

FIG. 2 is a plan view of the carriage;

FIG. 3 is a front view of the carriage;

FIG. 4 is an enlarged, sectional view of a portion of the drive means for operating the orbiting carriage member, as viewed in FIG. 3;

FIG. 5 is an enlarged, partial side elevation depicting in solid and phantom lines the curvilinear motion of the orbital carriage;

FIG. 6 is a plan view of FIG. 5 depicting the means of attachment and operation of the orbital carriage.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now in detail to the drawings, FIG. 1 shows a fork-lift truck shown generally at 10 and having a mast 12 of conventional construction mounted on a body 14. The orbital carriage of the instant invention, shown generally at 16, is of a type which is easily adapted to conventional fork-lift trucks, and is designed to easily replace the various standard carriages usually furnished with fork-lift trucks. The orbital carriage is controlled by the standard mast-lift and masttilt actuating and control mechanisms used with the standard carriage.

As may be seen in FIG. 1, the orbital carriage 16 is mounted to the mast 12 by means of a plurality of rollers 18 in a manner identical to that of the standard carriage which it replaces. The orbital carriage comprises a moving carriage 20 which is movable attached to a support carriage 22 by an upper and a lower cross shaft 24 and 26, respectively. The cross shafts extend transversely to the truck and carriage as may be seen in FIGS. 2 and 3.

As may be seen in FIG. 1, both the moving carriage 20 and the support carriage 22 include longitudinallyextending forks 28 and 30, respectively. An exemplary load 32 is shown in phantom being carried by supportcarriage forks 30.

Referring to FIG. 2, it may be seen that movingcarriage forks 28 are located in spaced relation to and intermediate support-carriage forks 30. These latter forks are interconnected by a wedge-Shaped, integral tip member 34.

Moving carriage 20 and forks 28 operate on apredetermined curvilinear path through the mechanism of eccentric journals 36 on the outer ends of rotatable cross shafts, as best seen in FIGS. 5 and 6. The four eccentric journals 36 of the cross shafts, of which only lower cross shaft 26 is shown, are phased in such a manner that the position of all such eccentrics is identical at all times, thus insuring their coordinated action and the subsequent curvilinear, oscillatory motion of moving carriage necessary to draw the-load onto itself, or by reversing the direction of rotation of .the'

cross shafts to discharge the load. It will be readily understood that the diameter of the aforementioned curvilinear path of the moving carriage 20 can be inturn, supply rotative power to the upper and lower shafts 24, 26. The resulting synchronized rotation of eccentric journals 36 causes the moving carriage 20 to move in a curvilinear plane in a counterclockwise direction, as viewed in FIG. 5. This is direction of curvilinearmotion for loading is such that generally horizon- I carriage 20 and against the vertical surfaces of said carcreased or decreased by increasing or decreasing, re- 7 V spectively, the maximum rise of all eccentrics 36 on cross shafts 24, 26.

The upper and lower cross shafts serve the dual purpose of providing motion to moving carriage 20 and connecting said carriage to support carriage 22. They are attached to carriage 20 by shaft journals 38 and mounting brackets 40 which are secured by a plurality of fasteners such as bolts 42. A

The outer ends of shafts 24, 26 are retained in the support carriage 22 by means of brackets 44 that are rigidly attached to the support carriage and are rotatably mounted in suitable bearings 46. The inner portions of shafts 24, 26 are rotatably supported in gearbox 48, as shown in FIG. 4.

The rotary motion of the shafts 24, 26 and their directly-associated eccentric journals is implemented by means of a gear train or power transmission means gene'rally shown at 50 and suitable motor means 52. The gear train can include idler gears 54, 56 that serve to transmit rotary motion fromthe motor means 52 to the upper cross shaft 24 and lower cross shaft (not shown) by means of drive gears 58 and 60 and would further serve to maintain the exact relationship between all eccentric journals. The lower cross shaft would have an identical gear train (not shown) for transmitting rotary motion. V r

In the alternative, a chain drive, or any other suitable drive means well known to those skilled in the. art,

riage. Forward movement of the lift truck during the orbital cycles of moving carriage 20 provides for a smooth' and systematic insertion of the support carriage 22, which supports the load while the moving carriage isreaching for the new position.

Although the motion of moving the forks under the load, and thereby the load, will be intermittent, the action will be made more positive by the use of a friction material on the top horizontal surfaces of the moving carriage forks 28. The top horizontal surfaces of support carriage forks 30, including its leading edge, are polished smooth for easier insertion of the member under the load ,as well as easier movement of the load onto the support carriage.

The unloading operation is the reverse of the aforementioned loading operation. Specifically, the operators control lever is movedto reverse position, which reverses the motor'means 52 and its associated drive meansofcross shafts 24, 26. The cross shafts and eccentric journals then rotate in a clockwise manner as could accomplish the same result as delivered by gear operation of the lift truck, may be controlled by means of a hand-- or foot-operated control lever (not shown) connected to a fluid'pressure control valve or an electrical switch, depending upon the motor means utilized.

In operation, the fork-lift truck approaches the load to be picked up and the polished, tapered leading edge or tip member 34 of support carriage 22 is inserted under the load by lowering the orbital carriage 20 to the ground and driving the truck into the load. The lift- 'truck operator moves the control lever to the load posi tion, thus actuating the motor means 52 and drive gear 58, idler gears 54, 56, and driven gears 60, which, in

viewed in FIG. 5, causing moving carriage 20 to travel in a clockwise, curvilinear path, thus moving the load off the support carriage forks 30. i

It is to be understood that the foregoing description invention and that the scope of the invention isnotto be limited thereto, but is to be determined by the scope of theappended, claims. I l I What is claimed is:

1. A self-loading and unloading orbital carriage attachment for use with a lift truck having a liftmast comprising 7 a support carriage comprising a generally vertical member having forks extending horizontally there'- from to define a load support surface, said forks of said support carriage being generally elongated members connected together by a transverse, integral tip member, of wedge-shaped cross section,

path relative to the;support carriage, said movable carriage comprisinga generally vertical member having forks extending horizontally therefrom to member,

movable carriage which is operable in a curvilinear eccentric means movable mounting said movable carriage relative to said support carriage whereby said movable carriage may operate in said curvilinear path,

and power means driving said eccentric means for causing said movable carriage to traverse said curvilinear path.

2. The invention of claim 1 wherein said eccentric means comprises rotatable cross shaft means having eccentric journal means thereon for supporting said movable carriage for curvilinear motion relative to said support carriage.

3. The invention of claim 2 wherein said power means includes motor means and a power transmission means intermediate said motor means and said cross shaft means, whereby said power transmission means transmits rotary motion from said motor means and said cross shaft means.

4. The invention of claim 3 wherein said motor means comprises a reversible motor having control means actuateable by an operator whereby said motor may be selectively operated in a forward direction to self-load and in a reverse direction to unload the orbital carriage.

5. The invention of claim 3 wherein said cross shaft means comprise a plurality of cross shafts rotatably mounted on said support carriage by mounting means, and wherein said power transmission means comprises a gear train, said gear train comprising a drive gear on said motor, a driven gear on each of said cross shafts and idler means interconnecting said drive and driven 1 riage forks.

, UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,737,060 Dated June 5, 1973 Inventor-(5) WALTER M. SHAFFER It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 6', Claim 6, line in, "alternatively" should be --alterna' cely-- Signed and sealed this 9th day of April 1971 (SEAL) Attest:

EDWARD I'-I.FLETCHER,JR. C. MARSHALL DANN Attesting Officer Commissioner of Patents USCOMM'DC 50376-P89 UIS. GOVERNMENT PRINTING OFFICE l9! O356-334 F ORM PO-IOSO (10-69) 

1. A self-loading and unloading orbital carriage attachment for use with a lift truck having a lift mast comprising: a support carriage comprising a generally vertical member having forks extending horizontally therefrom to define a load support surface, said forks of said support carriage being generally elongated members connected together by a transverse, integral tip member, of wedge-shaped cross section, a movable carriage which is operable in a curvilinear path relative to the support carriage, said movable carriage comprising a generally vertical member having forks extending horizontally therefrom to similarly define a load support surface, and wherein said forks of said movable carriage are of a length less than that of the forks of said support carriage and are dimensioned and positioned to be in spaced intermediate relationship to the forks of said support carriage, whereby said movable carriage forks may orbitally travel within the space defined by said support carriage forks and said tip member, eccentric means movable mounting said movable carriage relative to said support carriage whereby said movable carriage may operate in said curvilinear path, and power means driving said eccentric means for causing said movable carriage to traverse said curvilinear path.
 2. The invention of claim 1 wherein said eccentric means comprises rotatable cross shaft means having eccentric journal means thereon for supporting said movable carriage for curvilinear motion relative to said support carriage.
 3. The invention of claim 2 wherein said power means includes motor means and a power transmission means intermediate said motor means and said cross shaft means, whereby said power transmission means transmits rotary motion from said motor means and said cross shaft means.
 4. The invention of claim 3 wherein said motor means comprises a reversible motor having control means actuateable by an operator whereby said motor may be selectively operated in a forward direction to self-load and in a reverse direction to unload the orbital carriage.
 5. The invention of claim 3 wherein said cross shaft means comprise a plurality of cross shafts rotatably mounted on said support carriage by mounting means, and wherein said power transmission means comprises a gear train, said gear train comprising a drive gear on said motor, a driven gear on each of said cross shafts and idler means interconnecting said drive and driven gears.
 6. The invention of claim 1 wherein said eccentric means includes support means so positioned on said support carriage such that said forks of said moving carriage alternatively move above and below the load-support surface defined by said forks of said support surface when traversing the curvilinear path so as to intermittently engage and transport the load relative to the support carriage forks.
 7. The invention of claim 1 further including friction material fixed to the top surfaces of said movable carriage forks. 